621 高張力鋼板のレーザ曲げ加工(OS 塑性加工(5))

Abstract

SPFC590 high tensile strength steel sheets were V bent by means of laser forming. In bending high tensile strength steel sheet, great spring back is appeared and bending accuracy is low by conventional bending method, however, it is very easy to control the bending angle precisely by laser forming since laser forming does not employ a punch and die, and can change the working conditions such as laser power, scanning velocity and so on. A 300 W pulsed YAG laser was employed with the frequency of 300 Hz, scanning velocity of 100 mm/min and variation of bending angle were investigated by changing a laser power and scanning number. As the scanning number increases, the bending angle becomes greater linearly. When the laser power is in a range from 150 to 200 W, the bending angle is almost constant, but out of the range, the bending angle is lowered steeply.